The grain-eating red-billed quelea, a weaverbird species, is  considered the most serious bird pest in Africa.  On occasion occurring in flocks of millions of birds, it has a devastating impact on crops.

The estimated total quelea population is 1.5 billion birds and as such is thought to be the most numerous land-bird in the world.

There has not been any evidence of the quelea breeding in the winter rainfall area of the Western Cape until recently when Erna Rabie of Nuwerus farm between Worcester and Robertson noticed a flock of several hundred quelea, with males in breeding plumage, roosting in  the reeds on the Nuy River.

 As the birds were still present a week later Dr Dieter Oschadleus, who is a bird-ringing coordinator for Safring, decided to ring them.  He and birder Mike Ford, with the help of members of the Worcester Bird Club, ringed 116 quelea. There were 10 males, 9 females and 97 fledglings. Oschadleus estimated the population to be a few hundred. 

This breeding site in the Breede River Valley is not far from the Overberg wheat-growing area.

Ornithologists have alerted conservation and agricultural authorities confirming the presence of this breeding population of red-billed quelea near Worcester. There is great concern that if the quelea becomes established locally they will seriously affect the harvests of wheat and other grain crops with agriculture already under pressure from climate change.

Professor Les Underhill, director of the Animal Demography Unit in UCT’s Zoology Department, said, “If quelea get a grip on the Western Cape and start breeding in swarms that occur further north, they will become a major agricultural pest”.